This invention relates generally to electric coffeemakers, and more specifically to domestic electric coffeemakers in which a volume of water is heated in small increments and dripped through a spreader plate into a coffee grounds containing basket where the coffee brews and passes downwardly into a coffee carafe. These types of domestic coffeemakers are generally referred to as drip type coffeemakers.
In the last decade, the drip type coffeemaker has become the most popular type of coffeemaker in the U.S. market, largely displacing the vacuum type and percolator type coffeemakers which had theretofore been popular. Characteristically, the drip coffeemaker includes some type of easily filled reservoir which is connected by a conduit to water heating means with the discharge of the water heating means being connected to some sort of dispensing head which dispenses the heated water to a grounds containing brew basket. The dispensing head or the basket normally contains some sort of means to distribute the water across the bed of grounds, the means often being in the form of a spreader plate having apertures distributed above the coffee grounds. The water is normally fed by gravity to the heating means which then serves as a pump to raise the heated water upwardly, again to the level of the reservoir where it enters the water dispensing head. A check valve between the reservoir and the heating means allows the heating means to create steam or vapor which propels the heated water in the direction of the dispensing head.
It is conventional to associate the heating means in a hot plate type of structure on which the carafe for receiving the coffee liquor is positioned. Thus, the heating means serves to heat the water used for brewing the coffee and also to keep the brewed coffee warm. This basic type of drip coffeemaker has been well known in the art for several decades, and most of the development work during the intervening years has been directed toward improving the reliability and reducing the cost of manufacture of such coffeemakers.
Examples of prior art directed to drip type coffeemakers are the patents to Tarrant, et al. U.S. Pat. Nos. 3,589,271; Hollingsworth 4,083,295; Kyles 4,303,827; Flaherty, Jr., et al. 4,356,381; McLean 4,414,884; Marotta 4,402,257; and Amiot 4,467,707.
There are variations in the form taken by the drip coffeemakers now on the market insofar as the location of the coffee ground basket with respect to the carafe is concerned. As shown in the above-cited Flaherty, Jr., et al. U.S. Pat. No. 4,356,381, the coffee ground basket may be supported on the carafe for receiving the coffee liquor or, as in the case of the McLean U.S. Pat. No. 4,414,884 and Marotta U.S. Pat. No. 4,402,257, the coffee basket may be supported on the coffeemaker housing independent of the carafe. In either case, there have been concerns over containing within the system the vapors generated in connection with the heating of the water and the coffeemaking process in general. These vapors can damage the cabinetry above the coffeemaker and are thought to be useful to the flavor of the brew if they are retained in the system. The problem of retaining these vapors in the system has become of increased importance as a consequence of the popularity of coffeemakers which are adapted to be mounted in depending fashion immediately below the bottom of a kitchen cabinet. Co-pending application Ser. No. 722,941, filed Apr. 12, 1985, and assigned to the same assignee of the instant invention, discloses and claims an under-the-cabinet coffeemaker which includes means to seal the system and prevent the discharge of vapors generated in the system.
It has been commonplace to use plastic molded parts in connection with the drip type coffeemaker as illustrated in most of the above-cited patents. Most of the problems involved in drip type coffeemakers involve the water connections which are involved in the conduits transferring the water from the reservoir to the heating means and thence to the hot water dispensing head. Any simplification in the number and arrangement of these water conduits tends to substantially reduce the manufacturing cost of the coffeemaker and also to reduce the likelihood of malfunctions occurring.